1. Field of the Invention
The present invention relates to an absorbent composition of matter used to gradually release an active ingredient, such as a natural pesticide made from essential oils, for inhibiting the growth of bacteria, fungi and eradicating insect pests.
2. Description of the Related Art
Commercially available insecticides, including those available for home use, commonly comprise active ingredients or “poisons” which are not only toxic to the target insect pests, but, if used in relatively confined environments and delivered as aerosol sprays, can be present in sufficient concentration to also be toxic to humans and household pets. Various undesirable side effects may include immediate or delayed neurotoxic reactions, and/or suffocation. Even the noxious odor of such materials can cause headaches or upset stomachs in some individuals. These adverse side effects are exacerbated when such compositions come in contact with persons of increased sensitivity, or persons of small body mass such as children or babies.
For some time, efforts have been made to develop insecticidal compositions, particularly those intended for residential use in aerosol form, which are effective in killing the targeted insect pests completely and quickly, but non-toxic to humans and pets. The Environmental Protection Agency (EPA) regulates the use of potentially toxic ingredients in pesticidal compositions under the Federal Insecticide, Fungicide and Rodenticide Act. Certain materials considered to be either active or inert materials by the EPA have been deregulated or otherwise identified as acceptable “safe” substances offering minimum risk in normal use. Other materials are currently undergoing investigation and may be deregulated in due course. Deregulated substances are generally considered non-poisonous by the consumer. Thus, the term “non-poisonous” as used herein is intended to convey a composition that, while highly effective in killing targeted insect pests, is safe to use around humans, particularly small children, and pets.
Unfortunately, non-poisonous insecticidal compositions available heretofore incorporating deregulated materials as the active ingredient have had limited efficacy. Attempts to use deregulated essential oils as the active ingredient in such insecticides, while having limited success, have generally been found to be either cost prohibitive, inadequately lethal to control a range of targeted insect pest species, or too slow-acting to enable the user to confirm that the insect has been killed and to dispose of the dead insect so as to avoid polluting the environment.
Many commercial products contain components which exercise a beneficial effect for only a limited time after introduction into their intended environment, being rapidly consumed, metabolized, vaporized or otherwise lost. To have continued effectiveness, such products must be reapplied at intervals, providing an undesirable and perhaps harmful excess at the times of reapplication and barely adequate levels at later times.
Microencapsulation techniques address the problem of controlled release by enclosing the transient component within hollow shells of differing size and wall thickness, which dissolve or otherwise rupture at different intervals to provide a more or less steady supply.
The temporary shells of microencapsulation can be replaced by more permanent semipermeable shells which allow escape through the shell wall without shell destruction, or the entire microcapsule replaced by a homogeneous semipermeable vehicle containing the active ingredient as a pure impregnant, solute or precipitate. In this latter process, the host vehicle serves not to enclose the active ingredient within a wall, but as a carrier from which it can only slowly escape by solution, diffusion, evaporation or some other rate-limited process. The utility of a particular host material as such a carrier depends on such properties as liquid content, pore size, compatibility with various environments, surface energy and wettability, susceptibility to post-impregnation modifications in properties, and ease of manufacture in suitable physical forms. The commercial exploitation of slow release carrier vehicles requires the availability of inert, microporous materials which are readily impregnable with a wide variety of substances, have controllable porosity, and possess acceptable physical properties.
Garlic (Allium sativum Linn.) and/or its extract have been reported to have antibacterial and/or antifungal properties. It is known that Allicin isolated from the cloves of garlic had antibacterial properties against both Gram positive and Gram negative bacteria. Further, aqueous extracts of garlic have been reported to inhibit the growth of a variety of yeast-like fungi in the genera Candida, Cryptococcus, Rhudotoruto, Torulopsis and Trichosporon. It has also been previously reported that garlic extract and chips inhibit the growth of fungi such as Candida albicans, Aspergillus fumigatus and Aspergillus parasiticus. Because of its antifungal and antibacterial properties, garlic or its extract have been used as pesticides to control plant diseases such as mildew. It has also been used as an insecticide to control plant insects such as army worms, aphids and Colorado beetles. Most recently, garlic extract and water has been used to repel mosquitoes.
Therefore, there is a need in art for a safe, cost effective and highly efficient absorbent composition of matter that provides for a controlled time release of an aromatic substance, such as an essential oil or a combination of essential oils. One use of essential oils is to repel plagues of insects in the home as well as other agricultural crop damaging inserts.